Discontinuous reception procedures with enhanced component carriers

ABSTRACT

Methods, systems, and devices for wireless communication are described. Discontinuous reception (DRX) operation may be configured differently on enhanced component carriers (eCCs) than on other component carriers, including a primary cell (PCell). In some cases, a user equipment (UE) may be configured with several different eCC DRX modes. An eCC DRX configuration may, for example, be coordinated with downlink (DL) transmission time interval (TTI) scheduling so each DRX ON duration may correspond to a DL burst duration of the corresponding eCC. The eCC DRX ON durations may also be scheduled according to hybrid automatic repeat request (HARQ) process scheduling. In some examples, eCC DRX ON durations may be based on listen-before-talk (LBT) procedures. In some cases, eCC DRX ON durations may be configured to contain an uplink (UL) burst to enable channel state information (CSI) reporting. The eCC DRX may also be configured to minimize interruption of the PCell.

CROSS REFERENCES

The present application for patent is a Continuation application of U.S.patent application Ser. No. 16/411,428, entitled “DISCONTINUOUSRECEPTION PROCEDURES WITH ENHANCED COMPONENT CARRIERS,” filed May 14,2019 which is a Continuation application of U.S. patent application Ser.No. 15/042,491, entitled “DISCONTINUOUS RECEPTION PROCEDURES WITHENHANCED COMPONENT CARRIERS,” filed Feb. 12, 2016, which claims priorityto U.S. Provisional Patent Application No. 62/121,754, entitled “DRXProcedures with ECCS,” filed Feb. 27, 2015, assigned to the assigneehereof, and expressly incorporated by reference herein.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to discontinuous reception (DRX) procedures with enhancedcomponent carriers (eCCs). Wireless communications systems are widelydeployed to provide various types of communication content such asvoice, video, packet data, messaging, broadcast, and so on. Thesesystems may be capable of supporting communication with multiple usersby sharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code divisionmultiple access (CDMA) systems, time division multiple access (TDMA)systems, frequency division multiple access (FDMA) systems, andorthogonal frequency division multiple access (OFDMA) systems, (e.g., aLong Term Evolution (LTE) system). A wireless multiple-accesscommunications system may include a number of base stations, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

In some cases, a UE may communicate with a base station using multiplecomponent carriers in a carrier aggregation (CA) configuration. One ormore of the component carriers may be configured with a transmissiontime interval (TTI) that is different from the TTI of the primary cell(PCell). Using component carriers with different TTI lengths mayinterfere with operation in DRX mode, which may result in inefficientpower usage.

SUMMARY

Discontinuous reception (DRX) operation may be configured differently onenhanced component carriers (eCCs) than on a primary cell (PCell). Insome cases, a user equipment (UE) may be configured with severaldifferent eCC DRX modes based on whether the eCC DRX configuration iscoordinated with the PCell DRX configuration. For instance, an eCC DRXconfiguration may be coordinated with downlink (DL) TTI scheduling suchthat each DRX ON durations may correspond a DL burst duration of thecorresponding eCC. The eCC DRX ON durations may also be scheduledaccording to hybrid automatic repeat request (HARQ) process scheduling.In some examples, eCC DRX ON durations may be based onlisten-before-talk (LBT) procedures, such as clear channel assessment(CCA) procedures. In some examples, eCC DRX ON durations may beconfigured to contain (e.g., include) an uplink (UL) burst to enablechannel state information (CSI) reporting. The eCC DRX may alsoconfigured to minimize interruption of the PCell.

A method of wireless communication is described. The method may includedetermining a carrier aggregation (CA) configuration that includes afirst component carrier with a first channel usage procedure and asecond component carrier with a second channel usage procedure. Thefirst channel usage procedure may be different from the second channelusage procedure. In some cases, the method further includes determininga DRX configuration including a first configuration for the firstcomponent carrier and a second configuration for the second componentcarrier.

An apparatus for wireless communication is described. The apparatus mayinclude means for determining a CA configuration that includes a firstcomponent carrier with a first channel usage procedure and a secondcomponent carrier with a second channel usage procedure. The firstchannel usage procedure may be different from the second channel usageprocedure. The apparatus may also include means for determining a DRXconfiguration that includes a first configuration for the firstcomponent carrier and a second configuration for the second componentcarrier.

A further apparatus for wireless communication is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory and operable,when executed by the processor, to cause the apparatus to determine a CAconfiguration that includes a first component carrier with a firstchannel usage procedure and a second component carrier with a secondchannel usage procedure. The first channel usage procedure may bedifferent from the second channel usage procedure. The instructions mayalso be operable to cause the apparatus to determine a DRX configurationthat includes a first configuration for the first component carrier anda second configuration for the second component carrier.

A non-transitory computer-readable medium storing code for wirelesscommunication is described. The code may include instructions executableto determine a CA configuration that includes a first component carrierwith a first channel usage procedure and a second component carrier witha second channel usage procedure. The first channel usage procedure maybe different from the second channel usage procedure. The instructionsmay be further executable to determine a DRX configuration that includesa first configuration for the first component carrier and a secondconfiguration for the second component carrier.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the first channel usageprocedure is based at least in part on monitoring or transmitting usinga first transmission time interval (TTI) length and the second channelusage procedure is based at least in part on monitoring or transmittingusing a second TTI length different than the first TTI length. In someexamples the first TTI length is an LTE subframe and the second TTIlength is an LTE symbol period.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the second channel usageprocedure is based at least in part on a CCA procedure and the firstchannel usage procedure is based at least in part on a non-CCAprocedure. Additionally or alternatively, in some examples the secondcomponent carrier is in a shared or unlicensed spectrum. In someexamples, the second channel usage procedure is based at least in parton a listen-before-talk (LBT) procedure and the first channel usageprocedure is based at least in part on a non-LBT procedure.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the second configuration isbased at least in part on a channel acquisition timer. Additionally oralternatively, some examples may include processes, features, means, orinstructions for monitoring by a UE whether a channel has been acquiredby a base station during the channel acquisition timer, and for managingthe DRX configuration by the UE based on the monitoring. In some cases,the second configuration may be based at least in part on the channelacquisition timer.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for receiving a DRX initiation message,and initiating a DRX ON duration according to the second configurationbased at least in part on the DRX initiation message. Additionally oralternatively, in some examples the DRX initiation message istransmitted based at least in part on a CCA for the second carrier.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for receiving a DRX command message forthe second carrier on the first component carrier, and transitioning toa DRX OFF state on the second component carrier based at least in parton the DRX command message.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for deactivating at least one radiocomponent for communication on the second carrier for a first period oftime according to the second configuration, activating the radiocomponent for an ON duration after the first period of time has elapsed,and receiving a control channel message on the second carrier during theON duration. In some cases, the control channel message may indicate aburst length during the ON duration. Additionally or alternatively, someexamples may include processes, features, means, or instructions forreceiving an indication of a DL burst length during the ON duration.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for configuring a wireless device withthe CA configuration and the DRX configuration. Additionally oralternatively, some examples may include processes, features, means, orinstructions for transmitting an indication of a DL burst length duringan ON duration of the second configuration.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the DRX configurationincludes one or more DRX modes. Each mode may correspond to a relationbetween the first configuration and the second configuration.Additionally or alternatively, in some examples a mode of the one ormore DRX modes specifies that the first configuration is independent ofthe second configuration.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, a mode of the one or more DRXmodes includes a DRX ON duration of the second configuration associatedwith at least one DRX ON duration of the first configuration.Additionally or alternatively, in some examples a mode of the one ormore DRX modes specifies that the first configuration is independent ofthe second configuration during OFF durations of the first configurationand that a DRX ON duration of the second configuration associated witheach DRX ON duration of the first configuration.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the first component carrieris a primary cell (PCell) and the second component carrier is anenhanced component carrier (eCC) SCell. Additionally or alternatively,in some examples the first configuration is based at least in part on atleast one first DRX timer and the second configuration is based at leastin part on at least one second DRX timer.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, the second configurationcomprises a DL TTI associated with each ON duration of the secondconfiguration. Additionally or alternatively, in some examples the DLTTI associated with each ON duration of the second configuration isconfigured with DL control information directed toward the UE.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein, a DL burst configuration ofthe second component carrier includes a final DL TTI for each DL burstthat occurs during an ON duration of the second configuration.Additionally or alternatively, in some examples each ON duration of thesecond configuration is extended to include a final DL TTI for a DLburst of the second component carrier.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for receiving an indication of ascheduled UL burst during the final DL TTI of an ON duration of thesecond configuration, and transmitting an acknowledgement (ACK) for aHARQ process associated with the second carrier based at least in parton the indication. Additionally or alternatively, in some examples thesecond configuration includes an UL burst within an ON duration.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for transmitting a channel stateinformation (CSI) message using a TTI of the UL burst. Additionally oralternatively, in some examples the second configuration includes afirst set of ON durations co-extensive with a set of ON durations of thefirst configuration and a second set of ON durations within at least oneOFF duration of the first configuration.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for rating match a data transmission onthe first carrier based at least in part on symbol level interruption ofthe first carrier associated with an ON duration associated with thesecond configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be understood by reference to the following drawings:

FIG. 1 illustrates an example of a wireless communications system thatsupports discontinuous reception (DRX) procedures with enhancedcomponent carriers (eCCs) in accordance with various aspects of thepresent disclosure;

FIG. 2 illustrates an example of a wireless communications system thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure;

FIGS. 3-7 illustrate example timing diagrams for system operation thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure;

FIG. 8 illustrates an example of a process flow in a system thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure;

FIGS. 9-11 show block diagrams of a wireless device that supports DRXprocedures with eCCs in accordance with various aspects of the presentdisclosure;

FIG. 12 illustrates a diagram of a system including a UE that supportsDRX procedures with eCCs in accordance with various aspects of thepresent disclosure;

FIG. 13 illustrates a diagram of a system including a base station thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure; and

FIGS. 14-19 illustrate methods for DRX procedures with eCCs inaccordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Discontinuous reception (DRX) operation may be configured differently onenhanced component carriers (eCCs) than on a primary cell (PCell), asdescribed herein. The description herein includes illustrative examplesin the context of a wireless communication system, including examples ofdifferent aspects of eCC DRX configurations. For instance, a basestation may coordinate eCC ON durations with eCC downlink (DL) anduplink (UL) bursts to support active UE operation during certain symbolperiods, such as a pre-configured DL symbol, a first DL symbol in a DLburst, or a final DL symbol in a DL burst. This may enable the UE toreceive DL control information. A base station may also coordinate eCCscheduling and DRX to support UE awareness of UL burst availability forUL symbol transmission. Additionally, some of the described examplesillustrate an eCC DRX configuration designed to accommodatecommunication in shared or unlicensed spectrum using listen-before-talk(LBT) operations, when a UE may transmit channel state information(CSI), and how an eCC DRX configuration may be designed to manageinterference with a PCell. Other aspects of the description areillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that support DRX operation on eCCs.

FIG. 1 illustrates an example of a wireless communications system 100that supports DRX procedures with eCCs in accordance with variousaspects of the present disclosure. The wireless communications system100 includes base stations 105, UEs 115, and a core network 130. In someexamples, the wireless communications system 100 may be a Long TermEvolution (LTE)/LTE-Advanced (LTE-A) network.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more base station antennas. Each of the base stations 105 mayprovide communication coverage for a respective geographic coverage area110. The communication links 125 shown in wireless communications system100 may include UL transmissions from a UE 115 to a base station 105, orDL transmissions, from a base station 105 to a UE 115. The base stations105 may support, and may communicate with one another to support, DRXprocedures with eCCs. For example, the base stations 105 may interfacewith the core network 130 through backhaul links 132 (e.g., S1, etc.).The base stations 105 may also communicate with one another overbackhaul links 134 (e.g., X1, etc.) either directly or indirectly (e.g.,through core network 130). The base stations 105 may perform radioconfiguration and scheduling for communication with the UEs 115, or mayoperate under the control of a base station controller (not shown). Invarious examples, base stations 105 may be macro cells, small cells, hotspots, or the like. The base stations 105 may also be referred to aseNodeBs (eNBs) 105 in some examples.

The UEs 115 may be dispersed throughout the wireless communicationssystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso be referred to as a mobile station, a subscriber station, a remoteunit, a wireless device, an access terminal, a handset, a user agent, aclient, or some other suitable terminology. A UE 115 may also be acellular phone, a wireless modem, a handheld device, a personalcomputer, a tablet, a personal electronic device, a machine typecommunication (MTC) device or the like. The UEs 115 may communicate withbase stations 105, and may support DRX procedures with eCCs.

A UE may be configured with multiple carriers in carrier aggregation(CA) configuration, and the communication links 125 may represent suchmulticarrier CA configurations. A carrier may also be referred to as acomponent carrier (CC), a layer, a channel, etc. The term “componentcarrier” may refer to each of the multiple carriers utilized by a UE inCA operation, and may be distinct from other portions of systembandwidth. For instance, a component carrier may be a relativelynarrow-bandwidth carrier capable of being utilized independently or incombination with other component carriers. Each component carrier mayprovide the same capabilities as an isolated carrier based on release 8or release 9 of the LTE standard. Multiple component carriers may beaggregated or utilized concurrently to provide some UEs 115 with greaterbandwidth and, e.g., higher data rates. Thus, individual componentcarriers may be backwards compatible with legacy UEs 115 (e.g., UEs 115implementing LTE release 8 or release 9); while other UEs 115 (e.g., UEs115 implementing post-release 8/9 LTE versions), may be configured withmultiple component carriers in a multi-carrier mode. A carrier used forDL may be referred to as a DL CC, and a carrier used for UL may bereferred to as an UL CC. A UE 115 may be configured with multiple DL CCsand one or more UL CCs for carrier aggregation. Each carrier may be usedto transmit control information (e.g., reference signals, controlchannels, etc.), overhead information, data, etc.

Thus, a UE 115 may communicate with a single base station 105 utilizingmultiple carriers, and may also communicate with multiple base stations105 simultaneously on different carriers. Each cell of a base station105 may include an UL CC and a DL CC. The coverage area 110 of eachserving cell for a base station 105 may be different (e.g., CCs ondifferent frequency bands may experience different path loss). In someexamples, one carrier is designated as the primary carrier, or primarycomponent carrier (PCC), for a UE 115, which may be served by a primarycell (PCell). Primary cells may be semi-statically configured by higherlayers (e.g., radio resource control (RRC), etc.) on a per-UE basis.Certain uplink control information (UCI), e.g., ACK/NACK, channelquality indicator (CQI), and scheduling information transmitted onphysical uplink control channel (PUCCH), are carried by the primarycell. Additional carriers may be designated as secondary carriers, orsecondary component carriers (SCC), which may be served by secondarycells (SCells). Secondary cells may likewise be semi-staticallyconfigured on a per-UE basis. In some cases, secondary cells may notinclude or be configured to transmit the same control information as theprimary cell.

In some cases, wireless communications system 100 may utilize one ormore enhanced component carriers (eCCs). An eCC may be characterized byone or more features including: flexible bandwidth, differenttransmission time intervals (TTIs), and modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a sub-optimal backhaul link). An eCCmay also be configured for use in unlicensed spectrum or shared spectrum(e.g., where more than one operator is licensed to use the spectrum). AneCC characterized by flexible bandwidth may include one or more segmentsthat may be utilized by UEs 115 that are not capable of monitoring thewhole bandwidth or prefer to use a limited bandwidth (e.g., to conservepower).

In some cases, an eCC may utilize a different TTI length than other CCs,which may include use of a reduced or variable symbol duration ascompared with TTIs of the other CCs. The symbol duration may remain thesame, in some cases, but each symbol may represent a distinct TTI. Insome examples, an eCC may include multiple hierarchical layersassociated with the different TTI lengths. For example, TTIs at onehierarchical layer may correspond to uniform 1 ms subframes, whereas ina second layer, variable length TTIs may correspond to bursts of shortduration symbol periods. In some cases, a shorter symbol duration mayalso be associated with increased subcarrier spacing. In conjunctionwith the reduced TTI length, an eCC may utilize dynamic time-divisionduplex (TDD) operation (i.e., it may switch from DL to UL operation forshort bursts according to dynamic conditions).

Flexible bandwidth and variable TTIs may be associated with a modifiedcontrol channel configuration (e.g., an eCC may utilize an enhancedphysical downlink control channel (ePDCCH) for DL control information).For example, one or more control channels of an eCC may utilizefrequency-division multiplexing (FDM) scheduling to accommodate flexiblebandwidth use. Other control channel modifications include the use ofadditional control channels (e.g., for eMBMS scheduling, or to indicatethe length of variable length UL and DL bursts), or control channelstransmitted at different intervals. An eCC may also include modified oradditional HARQ related control information. A UE 115 may operate on aneCC, and other CCs, using discontinuous reception.

Discontinuous reception (DRX) may also be used in wirelesscommunications system 100 to conserve battery power at UEs 115. A DRXcycle may consist of an “ON duration” when the UE 115 may monitor forcontrol information (e.g., on PDCCH) and a “DRX period” when the UE 115may power down certain radio components. In some cases, DRX may conservepower at a UE 115 by allowing the UE 115 enter a low power state. The UE115 may monitor the physical downlink control channel (PDCCH) during ONdurations, which may be triggered by the expiration of a timer aftercommunications end during an ON duration, or by explicit signaling. Insome cases, a DRX ON duration, or DRX ON cycle, is referred to as aperiod or time during which a UE 115 is “awake.” So, in some cases, a UE115 that transitions from into an ON duration is said to “wake” or “wakeup.” Similarly, a UE 115 that enters a low power state associated with aDRX cycle may be said to “sleep” or to be “asleep.” Accordingly, in somecases, a UE 115 that transitions from an ON duration to a DRX period issaid to “go to sleep.” In a connected DRX mode (or connected mode DRX),a UE 115 may maintain an RRC connection with a base station 105 (e.g.,operate in RRC CONNECTED mode) while “sleeping” (e.g., powering downsome components) for some predetermined interval.

In some cases, a UE 115 may be configured with a short DRX cycle and along DRX cycle. A UE 115 may, for instance, enter a long DRX cycle if itis inactive for one or more short DRX cycles. The transition between theshort DRX cycle, the long DRX cycle and continuous reception may becontrolled by an internal timer or by messaging from a base station 105.A UE 115 may receive scheduling messages on PDCCH during the ONduration. While monitoring PDCCH for a scheduling message, the UE 115may initiate a DRX Inactivity timer. If a scheduling message issuccessfully received, the UE 115 may prepare to receive data and theDRX Inactivity timer may be reset. When the DRX Inactivity timer expireswithout receiving a scheduling message, the UE 115 may move into a shortDRX cycle and may start a DRX Short Cycle Timer. When the DRX ShortCycle Timer expires, the UE 115 may resume a long DRX cycle.

There may be a number of timers associated with a DRX configuration. Forexample, there may be long DRX parameters and short DRX parameters,which may be optional. The long DRX parameters may include an ONduration timer, which may be the duration in PDCCH subframes that the UE115 monitors PDCCH after waking up from DRX (e.g., 1-200 PDCCHsubframes). The long DRX parameters may further include a inactivitytimer, which may be the duration in PDCCH subframes that the UE 115waits to successfully decode a PDCCH, from the last successful decodingof a PDCCH for a new transmission (e.g., 0-2560 PDCCH subframes). Thelong DRX parameters may further include a long DRX cycle, which may bethe duration in subframes between successive ON duration cycles (e.g.,10-2560 subframes), and a DRX retransmission timer which may be theduration in DL subframes that the UE 115 monitors PDCCH when a HARQretransmission is pending (e.g., 1-33 subframes). The short DRXparameters may include a short DRX cycle (e.g., 2-640 subframes) and aDRX Short Cycle Timer (e.g., 1-16 cycles).

DRX operation may be configured differently on eCCs than on a PCell or anon-eCC SCell. For example, a UE 115 may be configured with severaldifferent eCC DRX modes based on whether the eCC DRX configuration iscoordinated with a PCell DRX configuration. The eCC DRX configurationmay also be coordinated to account for control communications such ashybrid automatic repeat request (HARQ), channel state information (CSI),and clear channel assessment (CCA) procedures, as described below. TheeCC DRX configuration may be based on timers similar to those of thePCell DRX timers described above, or may be based on a different set oftimers than those of the PCell.

FIG. 2 illustrates an example of a wireless communications system 200for DRX procedures with eCCs in accordance with various aspects of thepresent disclosure. Wireless communications system 200 may illustrateaspects of the wireless communications system 100. The wirelesscommunications system 200 includes base stations 105-a and 105-b thatmay be examples of aspects of the base station 105 described withreference to FIG. 1. The wireless communications system 200 alsoincludes a UE 115-a that may be an example of aspects of the UE 115described with reference to FIG. 1. In other examples, the wirelesscommunications system 200 includes other numbers of base stations 105and UEs 115.

The base stations 105-a and 105-b may communicate with UE 115-autilizing component carriers 225. One of component carriers 225 (e.g.,225-b) may be an enhanced component carrier (eCC). While not shown, a CAconfiguration may include several eCCs. The component carriers 225 mayinclude forward (e.g., DL) channels and reverse (e.g., UL) channels.Component carriers 225 can be in the same frequency operating band(intra-band) or in different operating bands (inter-band), andintra-band CCs can be contiguous or non-contiguous within the operatingband. Furthermore, one or more of the component carriers 225 can be inan unlicensed radio frequency spectrum band, which may be shared amongdifferent devices and operators of various systems. UE 115-a may beconfigured for DRX operation with different DRX configurationsassociated with the different component carriers 225. For example, eCC225-b may have a different DRX configuration from non-eCC cells.

One component carrier (CC) may be designated as the primary CC or PCell225-a for UE 115-a. PCell 225-a may be semi-statically configured byhigher layers (e.g., using radio resource control (RRC) signaling) on aper-UE basis. As mentioned, one or more of the other secondary cells(SCells) 225-c may be eCCs. Certain control information (e.g., HARQacknowledgements (ACKs), channel state information (CSI), DL/UL grants,scheduling requests (SR), etc.) related to data transmission on eCC maybe carried by the PCell 225-a. In some cases, the eCC DRX configurationfor eCC 225-b may be coordinated with a DRX configuration for PCell225-a, (e.g., to ensure that UE 115-a can transmit and receive theappropriate control information on PCell 225-a). In some examples, thePCell 225-a is a non-eCC LTE carrier. In some examples, SCells 225-b and225-c may both be eCC cells.

In some cases, UEs 115-a may achieve battery savings by limiting wake-uptime for DL control monitoring on eCC 225-b according to a DRXconfiguration. However, eCC 225-b may have a shorter TTI than PCell225-a, and may be configured for ultra-low latency (ULL) operation. Thatis, UE 115-a may have UL and DL subframes determined dynamically andscheduling may be performed bursts (e.g., in dynamically scheduledsequences of DL TTIs followed by a burst of UL TTIs). Furthermore, insome cases eCC 225-b may operate on an unlicensed carrier, which mayresult in further changes to the DRX configuration. Thus, the DRXconfiguration for eCC 225-b may be configured based on differentconsiderations. For example, DRX for eCC 225-b may be configured toaccommodate the bursty scheduling, ULL HARQ, CSI reporting, andlisten-before-talk (LBT) procedures (e.g., on an unlicensed spectrum).

Thus, the DRX configuration for UE 115-a may include multiple subconfigurations (e.g., for eCC 225-a and PCell 225-a) which may becoupled, partially coupled, or decoupled. For example, in some cases, UE115-a may be configured such that each PCell DRX ON state may correspondto at least one eCC DRX ON periods. As another example, the eCC DRXconfiguration may be completely independent from the PCell DRXconfiguration. The eCC DRX configuration may be based on eCC specificDRX timers, and the UE 115-a may be in a DRX ON state in eCC while in aDRX OFF state in PCC and vice versa.

FIG. 3 illustrates an example of a timing diagram 300 for a system thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure. Timing diagram 300 shows an eCC DRXconfiguration with pre-configured DL symbols to allow a UE 115 in DRXoperation to receive at least one DL symbol during each DRX ON duration.This may enable the UE 115 to receive DL control information. An eCC DRXconfiguration is shown along with the symbol type or transmission timeinterval (TTI) type. Timing diagram 300 may include a sequence ofsymbols 305, during which a UE 115 may deactivate one or more radiocomponent during DRX sleep periods (e.g., DRX periods, as describedabove) and then wake (e.g., wake up, as described above) to monitor theeCC during ON duration symbols 310. In some examples, the ON durationsymbols 310 may occur when an ON duration timer is active.

The UE 115 may not monitor the control channel (such as the PDCCH orePDCCH) during DRX sleep symbols (e.g., symbols during which a UE 115 isasleep) not included in the set of ON duration symbols 310. At times, ONduration symbols 310 and the other symbols 305 which occur before otherON duration symbols 310 may be considered a DRX cycle, which may berepeated (e.g., periodically). The symbol types may include DL symbols325 as well as UL symbols 320 from an base station 105.

A UE 115 may not know a priori if a symbol 305 is used for UL or DL whenit wakes for the ON duration symbols 310. Furthermore, it may bebeneficial for a UE 115 to ensure that at least one DL symbol isconfigured during each eCC ON duration 310. Thus, the eCC DRX may beconfigured such that certain pre-configured DL symbols 315 are scheduledwhile the UE 115 is in a DRX ON state. The pre-configured DL symbols 315may be predefined, signaled, determined in quasi-real time, ordetermined periodically. In some cases, the pre-configured DL symbols315 may be configured explicitly for a single UE 115. In some cases, thebase station 105 may provide at least one pre-configured DL symbol 315during certain wake-up periods (e.g., ON durations) for the UE 115.

FIGS. 4A, 4B, and 4C illustrate an example or examples of a timingdiagrams 401, 402, and 403 for systems that support DRX procedures witheCCs in accordance with various aspects of the present disclosure. Forinstance, wireless communications systems 100 and 200 of FIGS. 1 and 2may support communication according to timing diagrams 401, 402, and403. Timing diagrams 401, 402, and 403 illustrate alternatives that mayallow a UE 115 with an eCC DRX configuration to know when a DL burst isgoing to end (or, alternatively, when an UL burst will begin) in orderto determine whether a time for UL transmissions will become availableduring the DRX ON duration. The timing diagrams may include symbols 405which may include features of symbols 305 of FIG. 3, ON duration symbols410 which may include features of ON duration symbols 310 of FIG. 3, ULsymbols 420 which may include features of UL symbols 320 of FIG. 3, andDL symbols 425 which may include features of DL symbols 325 of FIG. 3.

At times, a UE may wake up in the middle of an ongoing burst of DLsymbols 425. This may prevent the UE from knowing when the DL burst 425will end. For example, the duration of the DL burst 425 may be signaledat the beginning of the DL burst 425. Further, the UE may not know whenthe subsequent UL burst 420 starts, which may be interfere with theability to transmit an uplink control information (UCI) or hybridautomatic repeat request (HARQ) transmission.

HARQ may be a method of ensuring that data is received correctly over awireless communication link. HARQ may include a combination of errordetection (e.g., using a cyclic redundancy check (CRC)), forward errorcorrection (FEC), and retransmission (e.g., a hybrid automatic repeatrequest (HARQ)). HARQ may improve throughput at the media access control(MAC) layer in poor radio conditions (e.g., signal-to-noise conditions).In Incremental Redundancy HARQ, incorrectly received data may be storedin a buffer and combined with subsequent transmissions to improve theoverall likelihood of successfully decoding the data. In some cases,redundancy bits are added to each message prior to transmission. Thismay be especially useful in poor conditions. In other cases, redundancybits are not added to each transmission, but are retransmitted after thetransmitter of the original message receives a negative-acknowledgment(NACK) indicating a failed attempt to decode the information. If a UE115 wakes-up in the middle of an ongoing burst, the UE 115 may not knowwhen it may send UL transmissions relating to UCI or HARQ. For example,a UE may locate an ACK resource, such as based on the beginning or endof a burst, and wake-up for its transmission or reception. Further, insome cases if UE 115 reports UL ACK, the UE 115 may return to a DRXsleep state, and otherwise the UE 115 may wake-up after a HARQ roundtrip time (RTT) for a possible retransmission grant, and may remainawake during the duration of a retransmission timer.

According to the example of FIG. 4A, a base station 105 may adjust theduration of bursts, such that the bursts terminate or start when the UE115 is in a DRX ON state. The base station 105 may adjust the durationof bursts based on the status of the UE 115. By adjusting the durationof bursts, the base station 105 may ensure that ON duration symbols 410overlap with the beginning or end of a DL burst 425 (or in some cases,an UL burst 420), therefore enabling the UE 115 to receive controlinformation relating to the DL burst 425 or the UL burst 420. Forexample, this may enable the UE 115 to receive a PDCCH transmissionduring a DRX ON duration 410.

According to the example of FIG. 4B, a UE 115 may wake-up for a DRX ONduration and stay awake until the end of a DL burst is detected. Forexample, the UE 115 may be scheduled to use ON duration symbols 410-a,which may include features of the ON duration symbols 410 of FIG. 4A.During this period the UE 115 may monitor PDCCH during the DRX ON state,and the ON duration symbols 410-a may be extended into additional ONduration symbols 435. Additional ON duration symbols 435 may extend theON duration until the end of a burst is detected, such as DL burst425-a. In some cases, if the UE 115 is scheduled during its DRX ONstate, it may receive a DRX command (e.g., via a MAC control element) toreturn to a DRX sleep state. In some cases, the additional ON durationsymbols 435 may overlap with one or more symbols of a next burst period,such as UL burst 420-a, which may include features of UL burst 420 ofFIG. 4A. In some cases, the ON duration may stop before overlapping withan UL burst period (e.g., UL burst 420-a). In some cases, the UE 115 maymonitor the channel to receive a DL burst indication 430 for a DLtransmission indicating how long the DL burst will last. This may enablethe UE 115 to add the additional ON duration symbols 435.

According to the example of FIG. 4C, a UE 115 may acquire a burst lengthindication (e.g., via a PDCCH or ePDCCH) and add an additionalnon-contiguous TTI to an ON duration. For example, a DL burst indication430-a may be transmitted to the UE 115 by a base station 105. Theindication may be dedicated signaling, or it may be signaled to a groupUEs 115 using a dedicated physical (PHY) broadcast channel. The lengthindication may indicate the end of a DL burst period to the UE 115 ifthe UE 115 misses the control channel containing the burst scheduling.The UE 115 may then wake up for the original ON duration symbols 410-band wake up again for an additional period. In some cases, the UE 115may receive a length indication during the middle of a DL burst duringthe ON duration symbols 410-b or when the UE 115 is in a DRX ON state(e.g., awake). The length indication may be used to determine a time forthe UE 115 to be in a DRX ON state.

For example, the UE 115 may wake up during additional ON durationsymbols 435-a. The additional ON duration symbols 435-a may overlap withthe end of a DL burst (such as DL burst 425-b) or the beginning of an ULburst (such as UL burst 420-b). By receiving the length indication andadding a single symbol at the end of DL burst 425-b, the UE 115 mayreduce the number of additional ON duration symbols 435-a—e.g., comparedto remaining in an active state during the intermediate symbols betweenthe ON duration symbols 410 and the additional ON duration symbols 435.

FIGS. 5A and 5B illustrate examples timing diagrams 501 and 502 forsystems that support DRX procedures with eCCs in accordance with variousaspects of the present disclosure. For instance, wireless communicationssystems 100 and 200 of FIGS. 1 and 2 may support communication accordingto timing diagrams 501 and 502. Timing diagrams 501 and 502 representeCC DRX configurations for communication over shared or unlicensedspectrum using listen-before-talk (LBT) operations. Timing diagrams 501and 502 may include symbols 505 which may include features of symbols405 of FIGS. 4A, 4B and 4C, ON duration symbols 510 which may includefeatures of ON duration symbols 410, UL symbols 520 which may includefeatures of UL symbols 420, DL symbols 525 which may include features ofDL symbols 425, and additional ON duration symbols 535 which may includefeatures of additional ON duration symbols 435 as described herein withreference to FIGS. 4A, 4B and 4C.

In some cases, a UE 115 or base station 105 may operate in a shared orunlicensed frequency spectrum. These devices may perform a CCA prior tocommunicating in order to determine whether the channel is available. ACCA may include an energy detection procedure to determine whether thereare any other active transmissions. For example, the device may inferthat a change in a received signal strength indication (RSSI) of a powermeter indicates that a channel is occupied. Specifically, signal powerthat is concentrated in a certain bandwidth and exceeds a predeterminednoise floor may indicate the presence of another wireless transmitter. ACCA may also include detection of a pre-determined or randomly selectedsequence with features that indicate use of the channel. For example,another device may transmit a specific preamble prior to transmitting adata sequence. In some cases, a CCA may be a part of alisten-before-talk (LBT) configuration.

In shared or unlicensed spectrum operation, a base station 105 may notbe able to capture the channel during a DRX ON state to schedule the UE115. The base station 105 may need to follow certain LBT procedures,such as a CCA or enhanced CCA (eCCA), to determine whether the channelis available. It may be preferable for the UE 115 to be in a DRX ONstate when the channel is available, however, the UE 115 may not knowwhen the base station 105 has successfully captured the channel when itwakes up. In some cases, the base station 105 may configure anadditional timer, such as a channel acquisition timer, so that the UE115 may remain awake long enough to determine whether the channel iscaptured. If the channel is not captured, the UE 115 may return to a DRXsleep state.

According to the example of FIG. 5A, a base station 105 may configuremultiple timers, such as multiple eCC DRX timers. For example, the basestation 105 may configure a first timer which may be used to detectwhether the base station 105 has captured the channel. A second timermay be used for ensuring a sufficiently long DRX ON duration if thechannel is available. In some cases, if the UE 115 detects that the basestation 105 has acquired a channel during the first timer (e.g., byreceiving a channel acquisition indication), the second timer may bestarted. The UL/DL symbol type portion of timing diagram 501 may includean uncaptured channel period 540 during which the base station 105 doesnot have the channel. For example, the uncaptured channel period 540 mayinclude symbols during which the serving base station 105 failed a CCAor eCCA, or symbols before a CCA or eCCA was successful.

In some cases, the UE 115 make wake up during ON duration symbols 510and start the first timer. For example, the UE 115 may awake duringuncaptured channel period 540. The base station 105 may have a clearchannel and may transmit a DL burst 525. The UE 115 may detect that thechannel is clear prior to the expiration of the channel expiration timerand the second timer may be initiated. The combination of the first andsecond timers may result in additional ON duration symbols 535 beingadded to the ON duration symbols 510 based on the duration of the secondtimer. The additional ON duration symbols 535 may allow the UE 115 todetect the beginning and/or end of a burst, such as UL burst 520 or DLburst 525. If the UE 115 does not detect a clear channel during thefirst timer (corresponding to ON duration symbols 510), the UE 115 mayreturn to sleep. That is, the second timer may not be started andadditional ON duration symbols 535 may not be added to the ON durationsymbols 510.

According to the example of FIG. 5B, an explicit DRX ON command may beused to activate a UE 115 when a base station 105 has captured a channeland is ready to communicate. That is, during a period when the channelis not captured (uncaptured channel period 540-a), the base station 105may perform a CCA and then indicate that the channel is captured to theUE 115. In some examples, the command may be transmitted via a primarycell (PCell). The UE 115 may wake-up, or start ON duration symbols510-a, based on reception of the DRX ON command. In some cases when aDRX ON command is used, eCC DRX operation may be asynchronous. That is,it may not be based on a DRX cycle. For example, the UE 115 may not wakefor ON duration symbols 510-a without reception of a command.

FIG. 6 illustrates an example of a timing diagram 600 for systems thatsupport DRX procedures with eCCs in accordance with various aspects ofthe present disclosure. For instance, wireless communications systems100 and 200 of FIGS. 1 and 2 may support communication according totiming diagram 600. Timing diagram 600 may illustrate an example of whena UE 115 may transmit channel state information (CSI) during eCC DRXoperation. Timing diagram 600 may include symbols 605, ON durationsymbols 610, UL symbols 620, DL symbols 625, and grant symbol 630 whichmay include features of corresponding symbols of FIGS. 3-5.

A base station 105 may gather channel condition information from a UE115 in order to efficiently configure and/or schedule the channel. Thisinformation may be sent from the UE 115 in the form of a channel statereport. A channel state report may contain a rank indicator (RI)requesting a number of layers to be used for DL transmissions (e.g.,based on the antenna ports of the UE 115), a precoding matrix indicator(PMI) indicating a preference for which precoder matrix should be used(based on the number of layers), and a channel quality indicator (CQI)representing the highest modulation and coding scheme (MCS) that may beused. CQI may be calculated by a UE 115 after receiving predeterminedpilot symbols such as cell-specific reference signals (CRS) or CSIreference signal. RI and PMI may be excluded if the UE 115 does notsupport spatial multiplexing (or is not in a mode that supports spatialmultiplexing). The types of information included in the reportdetermines a reporting type. Channel state reports may be periodic oraperiodic. That is, an base station 105 may configure a UE 115 to sendperiodic reports at regular intervals, and may also request additionalreports as needed. Aperiodic reports may include wideband reportsindicating the channel quality across an entire cell bandwidth, UE 115selected reports indicating a subset of the preferred subbands, orconfigured reports in which the subbands reported are selected by thebase station 105.

A UE 115 may not transmit CSI unless it is awake during an UL burst.Thus, to allow CSI transmission when using DRX, an base station 105 mayconfigure DRX so that an UL burst 620 occurs while the UE 115 is awake,such as during a DRX ON state. For example, CSI transmission may besuppressed unless ON duration symbols 610 overlap with, or contain, anUL burst 620. It should be noted that the ON duration symbols 610 mayfully contain the UL burst 620, or may overlap with a subset of the ULburst 620. In some cases, UL symbols 620 do not increment the DRXtimers. That is, a UE 115 may suspend an eCC DRX timer during UL symbols620 and resume the eCC DRX timer during the first symbol period of thenext set of DL symbols 625.

FIG. 7 illustrates an example of a timing diagram 700 in systems thatsupport DRX procedures with eCCs in accordance with various aspects ofthe present disclosure. For instance, wireless communications systems100 and 200 of FIGS. 1 and 2 may support communication according totiming diagram 700. Timing diagram 700 may represent an eCC DRXconfiguration for mitigating interference with a PCell. Timing diagram700 may include symbols 705 and ON duration symbols 710 which mayinclude features described herein with reference to FIGS. 3-6. Timingdiagram 700 may also include PCell sleep period 715 and PCell ONduration 720.

In some cases, a different DRX configuration for an eCC and a PCell mayresult in an interruption in communication with the PCell. Theinterruption of the PCell may be caused by DRX transitions from onperiods to off periods, or vice versa, on an eCC SCell. This may resultin loss of data symbols on the PCell (e.g., a loss of 1 TTI forinter-band or 5 TTIs for intra-band communications). Thus, frequent DRXtransitions on an eCC may cause a large number of interruptions on thePCell.

To avoid PCell interruptions, the eCC DRX cycle may only apply duringPCell sleep periods 715, while during other periods, such as PCell ONduration 720, the DRX cycle of the UE 115 may be coordinated with thePCell DRX configuration. Additionally or alternatively, an eCC capableUE 115 may indicate support for symbol-level interruption on the PCell(e.g., via RRC messaging). In some cases, the interruption caused by afew symbols may not compromise the entire PCell TTI. Thus, rather thanlimiting eCC DRX to PCell sleep periods 715, PCell transmissions may berate-matched around interrupted symbols.

FIG. 8 illustrates an example of a process flow 800 within a system thatsupports DRX procedures with eCCs in accordance with various aspects ofthe present disclosure. Process flow 800 may include communicationsbetween a UE 115-b and a base station 105-c, which may be examples of aUE 115 and base station 105 described herein with reference to FIGS.1-2.

At 205, UE 115-b and base station 105-c may establish a carrieraggregation (CA) configuration. Each device may determine theconfiguration including a first component carrier with a first channelusage procedure and a second component carrier with a second channelusage procedure; the first channel usage procedure may be different fromthe second channel usage procedure. In some examples, the first channelusage procedure is based on monitoring or transmitting using a first TTIlength and the second channel usage procedure is based on monitoring ortransmitting using a second TTI length different than the first TTIlength. The first TTI length may, for example, be an LTE subframe andthe second TTI length may be an LTE symbol period. In some examples, thesecond component carrier is in a shared or unlicensed spectrum. In someexamples, the second channel usage procedure is based at least in parton an LBT procedure and the first channel usage procedure is based atleast in part on a non-LBT procedure. In some examples, the firstcomponent carrier is a PCell and the second component carrier is an eCCSCell.

In some cases, the second channel usage procedure may be based on a CCAprocedure and the first channel usage procedure may not be based on aCCA procedure. Thus, UE 115-b may monitor whether a channel has beenacquired by base station 105-c during the channel acquisition timer andmanage the DRX configuration based on the monitoring. In some cases, UE115-b may receive a DRX initiation message and initiate a DRX ONduration according to the second configuration based at least in part onthe DRX initiation message. The DRX initiation message may betransmitted by base station 105-c based at least in part on a CCA forthe second carrier. UE 115-b may receive a DRX command message for thesecond carrier on the first component carrier and transition to a DRXOFF state on the second component carrier based at least in part on theDRX command message.

At 210, UE 115-b and base station 105-c may establish a DRXconfiguration. Each device may determine a DRX configuration including afirst configuration for the first component carrier and a secondconfiguration for the second component carrier. In some cases, (e.g., ifUE 115-b and base station 105-c are communicating using unlicensedspectrum) the second configuration is based on a channel acquisitiontimer. Thus, base station 105-c may configure UE 115-b with the CAconfiguration and the DRX configuration. In some examples, the DRXconfiguration includes one or more DRX modes, and each mode maycorrespond to a relation between the first configuration and the secondconfiguration. A DRX mode may specify that the first configuration isindependent of the second configuration. In some examples, a mode of theone or more DRX modes includes a DRX ON duration of the secondconfiguration associated with at least one DRX ON duration of the firstconfiguration. In some examples, a DRX mode may specify that the firstconfiguration is independent of the second configuration during OFFdurations of the first configuration and that a DRX ON duration of thesecond configuration associated with each DRX ON duration of the firstconfiguration.

In some examples, the first configuration may be based on one DRX timerand the second configuration may be based on a different DRX timer. Insome examples, the second configuration includes a DL TTI associatedwith each ON duration of the second configuration. Additionally oralternatively, the DL TTI associated with each ON duration of the secondconfiguration may be configured with DL control information directedtoward the UE 115. In some cases, a DL burst configuration of the secondcomponent carrier includes a final DL TTI for each DL burst that occursduring an ON duration of the second configuration. Each ON duration ofthe second configuration may be extended to include a final DL TTI for aDL burst of the second component carrier. In some examples, the secondconfiguration includes a first set of ON durations co-extensive with aset of ON durations of the first configuration and a second set of ONdurations within at least one OFF duration of the first configuration.

At 215, UE 115-b may deactivate a radio (or a radio component) based onthe DRX configuration for the eCC. For example, UE 115-b may deactivateat least one radio component for communication on the second componentcarrier according to the second configuration.

At 220, UE 115-b may activate the radio (or radio component) based onthe DRX configuration for the eCC. UE 115-b may activate the at leastone radio component for an ON duration according to the secondconfiguration. In some cases, (e.g., if UE 115-b and base station 105-care communicating using unlicensed spectrum) UE 115-b may receive a DRXinitiation message from base station 105-c on the first componentcarrier based on a CCA for the second component carrier. Then UE 115-bmay initiate a DRX ON duration according to the second configuration(i.e., for the eCC) based on the DRX initiation message. In some cases,the activation of the radio may interfere with communication on a PCelland base station 105-c may rate match a data transmission on the firstcomponent carrier based on symbol level interruption of the firstcomponent carrier associated with an ON duration associated with thesecond configuration.

The UE may detect the CCA without an explicit DRX initiation message inthe first carrier, e.g., by monitoring a reference signal on the secondcarrier during the channel acquisition timer. The UE may initiate a DRXON operation according to the second configuration based on the CCAdetection. The UE may receive, for the second carrier, a DRX commandmessage from the base station. The DRX command message may be sent onthe first carrier. The UE may transition to a DRX OFF state on thesecond carrier based on the DRX command message, regardless of the DRXconfiguration on the first carrier.

At 225, UE 115-b may receive a control message (such as a PDCCH orePDCCH) from base station 105-c during an eCC DL burst. Thus, UE 115-bmay receive a control channel message on the second component carrierduring the ON duration. In some cases, UE 115-b may receive anindication of a DL burst length from base station 105-c during the ONduration. In some examples, UE 115-b may receive an indication of ascheduled UL burst during the final DL TTI of an ON duration of thesecond configuration.

At 230, UE 115-b may receive data from base station 105-c based on agrant in the control message during the eCC DL burst. At 235, UE 115-bmay transmit an UL to base station 105-c during a subsequent UL burst.In some cases, UE 115-b may transmit an ACK for a HARQ processassociated with the second component carrier based on the indication. Insome examples the second configuration includes an UL burst within an ONduration. In some cases, UE 115-b may transmit a CSI message using a TTIof the UL burst. At 240, UE 115-b may deactivate the radio (or radiocomponent) for the next DRX sleep period.

Next, FIG. 9 shows a block diagram of a wireless device 900 configuredfor DRX procedures with eCCs in accordance with various aspects of thepresent disclosure. Wireless device 900 may be an example of aspects ofa UE 115 or base station 105 described with reference to FIGS. 1-8.Wireless device 900 may include a receiver 905, an eCC DRX module 910,or a transmitter 915. Wireless device 900 may also include a processor.Each of these components may be in communication with one another.

The receiver 905 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to DRXprocedures with eCCs, etc.). Information may be passed on to the eCC DRXmodule 910, and to other components of wireless device 900. For example,the receiver 905 may receive a DRX initiation message on the firstcomponent carrier based on a CCA for the second component carrier. Insome examples, the receiver 905 may receive a control channel message onthe second component carrier during the ON duration. In some case, thereceiver 905 may receive an indication of a DL burst length during theON duration. Additionally or alternatively, the receiver 905 may receivean indication of a scheduled UL burst during the final DL TTI of an ONduration of the second configuration.

The eCC DRX module 910 may determine a CA configuration, which mayinclude a first component carrier with a first channel usage procedureand a second component carrier with a second channel usage procedure.The first channel usage procedure may be different from the secondchannel usage procedure. The eCC DRX module 910 may also determine a DRXconfiguration, which may include a first configuration for the firstcomponent carrier and a second configuration for the second componentcarrier.

The transmitter 915 may transmit signals received from other componentsof wireless device 900. In some examples, the transmitter 915 may becollocated with the receiver 905 in a transceiver module. Thetransmitter 915 may include a single antenna, or it may include aplurality of antennas. In some examples, the transmitter 915 maytransmit an indication of a DL burst length during an ON duration of thesecond configuration.

FIG. 10 shows a block diagram of a wireless device 1000 for DRXprocedures with eCCs in accordance with various aspects of the presentdisclosure. Wireless device 1000 may be an example of aspects of awireless device 900 or a UE 115 or base station 105 described withreference to FIGS. 1-9. Wireless device 1000 may include a receiver905-a, an eCC DRX module 910-a, or a transmitter 915-a. Wireless device1000 may also include a processor. Each of these components may be incommunication with one another. The eCC DRX module 910-a may alsoinclude a CA configuration module 1005, and a DRX configuration module1010.

The receiver 905-a may receive information which may be passed on to eCCDRX module 910-a, and to other components of wireless device 1000. TheeCC DRX module 910-a may perform the operations described herein withreference to FIG. 9. The transmitter 915-a may transmit signals receivedfrom other components of wireless device 1000.

The CA configuration module 1005 may determine a CA configurationincluding a first component carrier with a first channel usage procedureand a second component carrier with a second channel usage procedure asdescribed herein with reference to FIGS. 2-8. The first channel usageprocedure may be different from the second channel usage procedure. TheCA configuration module 1005 may also configure a wireless device withthe CA configuration and the DRX configuration. In some examples, thefirst component carrier may be a PCell and the second component carriermay be an eCC secondary cell (SCell).

The DRX configuration module 1010 may determine a DRX configurationincluding a first configuration for the first component carrier and asecond configuration for the second component carrier as describedherein with reference to FIGS. 2-8. In some examples, the DRXconfiguration includes one or several DRX modes, such that each mode maycorrespond to a relation between the first configuration and the secondconfiguration. In some examples, a DRX mode specifies that the firstconfiguration may be independent of the second configuration. In someexamples, a DRX mode includes a DRX ON duration of the secondconfiguration associated with a DRX ON duration of the firstconfiguration. In some examples, a DRX mode may specify that the firstconfiguration is independent of the second configuration during OFFdurations of the first configuration and that a DRX ON duration of thesecond configuration associated with each DRX ON duration of the firstconfiguration.

The first configuration described herein may be based on one DRX timerand the second configuration may be based on a different DRX timer. Insome examples, the second configuration includes a DL TTI associatedwith each ON duration of the second configuration. In some examples, theDL TTI associated with each ON duration of the second configuration maybe configured with DL control information directed toward the UE 115. Insome cases, a DL burst configuration of the second component carrier mayinclude a final DL TTI for each DL burst that occurs during an ONduration of the second configuration. Each ON duration of the secondconfiguration may be extended to include a final DL TTI for a DL burstof the second component carrier. In some examples, the secondconfiguration includes an UL burst within an ON duration. The secondconfiguration may include a first set of ON durations co-extensive witha set of ON durations of the first configuration and a second set of ONdurations within at least one OFF duration of the first configuration.

FIG. 11 shows a block diagram 1100 of an eCC DRX module 910-b which maybe a component of a wireless device 900 or a wireless device 1000 forDRX procedures with eCCs in accordance with various aspects of thepresent disclosure. The eCC DRX module 910-b may be an example ofaspects of an eCC DRX module 910 described with reference to FIGS. 9-10.The eCC DRX module 910-b may include a CA configuration module 1005-a,and a DRX configuration module 1010-a. Each of these modules may performthe functions described herein with reference to FIG. 10. The eCC DRXmodule 910-b may also include a TTI length manager 1105, a CCA module1110, a DRX wake module 1115, a DRX sleep module 1120, a HARQ module1125, and a rate matching module 1130.

The TTI length manager 1105 may configure or be configured to determinea first channel usage procedure based on monitoring or transmittingusing a first transmission TTI length and a second channel usageprocedure based on monitoring or transmitting using a second TTI lengthdifferent than the first TTI length, as described herein with referenceto FIGS. 2-8. In some examples, the first TTI length may be an LTEsubframe and the second TTI length may be an LTE symbol period.

The CCA module 1110 may configure or be configured to determine a secondchannel usage procedure based on a CCA procedure and a first channelusage procedure not based on a CCA procedure, as described herein withreference to FIGS. 2-8. In some examples, the second component carriermay be in a shared or unlicensed spectrum. In some examples, the secondconfiguration may be based on a channel acquisition timer. The DRX wakemodule 1115 may initiate a DRX ON duration according to the secondconfiguration based on the DRX initiation message as described hereinwith reference to FIGS. 2-8. The DRX wake module 1115 may also activatethe at least one radio component for an ON duration according to thesecond configuration.

The DRX sleep module 1120 may deactivate at least one radio componentfor communication on the second component carrier according to thesecond configuration as described herein with reference to FIGS. 2-8.The HARQ module 1125 may transmit an ACK for a HARQ process associatedwith the second component carrier based on the indication as describedherein with reference to FIGS. 2-8. The rate matching module 1130 mayrate match a data transmission on the first component carrier based onsymbol level interruption of the first component carrier associated withan ON duration associated with the second configuration as describedherein with reference to FIGS. 2-8.

FIG. 12 shows a diagram of a system 1200 including a UE 115 configuredfor DRX procedures with eCCs in accordance with various aspects of thepresent disclosure. System 1200 may include UE 115-c, which may be anexample of a wireless device 900, a wireless device 1000, or a UE 115described herein with reference to FIGS. 1, 2, and 9-11. UE 115-c mayinclude an eCC DRX module 1210, which may be an example of an eCC DRXmodule 910 described with reference to FIGS. 9-11. UE 115-c may alsoinclude a CSI module 1225. UE 115-c may also include components forbi-directional voice and data communications including components fortransmitting communications and components for receiving communications.For example, UE 115-c may communicate bi-directionally with base station105-d or base station 105-e, which may support different componentcarriers of a carrier aggregation configuration. The CSI module 1225 maytransmit a CSI message using a TTI of the UL burst as described hereinwith reference to FIGS. 2-8.

UE 115-c may also include a processor 1205, and memory 1215 (includingsoftware (SW) 1220), a transceiver 1235, and one or more antenna(s)1240, each of which may communicate, directly or indirectly, with oneanother (e.g., via buses 1245). The transceiver 1235 may communicatebi-directionally, via the antenna(s) 1240 or wired or wireless links,with one or more networks, as described above. For example, thetransceiver 1235 may communicate bi-directionally with a base station105 or another UE 115. The transceiver 1235 may include a modem tomodulate the packets and provide the modulated packets to the antenna(s)1240 for transmission, and to demodulate packets received from theantenna(s) 1240. While UE 115-c may include a single antenna 1240, UE115-c may also have multiple antennas 1240 capable of concurrentlytransmitting or receiving multiple wireless transmissions.

The memory 1215 may include random access memory (RAM) and read onlymemory (ROM). The memory 1215 may store computer-readable,computer-executable software/firmware code 1220 including instructionsthat, when executed, cause the processor 1205 to perform variousfunctions described herein (e.g., DRX procedures with eCCs, etc.).Alternatively, the software/firmware code 1220 may not be directlyexecutable by the processor 1205 but cause a computer (e.g., whencompiled and executed) to perform functions described herein. Theprocessor 1205 may include an intelligent hardware device, (e.g., acentral processing unit (CPU), a microcontroller, an ASIC, etc.).

FIG. 13 shows a diagram of a system 1300 including a base station 105configured for DRX procedures with eCCs in accordance with variousaspects of the present disclosure. System 1300 may include base station105-f, which may be an example of a wireless device 900, a wirelessdevice 1000, or a base station 105 described herein with reference toFIGS. 1, 2, and 10-12. Base station 105-f may include a base station eCCDRX module 1310, which may be an example of a base station eCC DRXmodule 1310 described with reference to FIGS. 10-12. Base station 105-fmay also include components for bi-directional voice and datacommunications including components for transmitting communications andcomponents for receiving communications. For example, base station 105-fmay communicate bi-directionally with UE 115-d or UE 115-e.

In some cases, base station 105-f may have one or more wired backhaullinks. Base station 105-f may have a wired backhaul link (e.g., S1interface, etc.) to the core network 130. Base station 105-f may alsocommunicate with other base stations 105, such as base station 105-g andbase station 105-h via inter-base station backhaul links (e.g., an X2interface). Each of the base stations 105 may communicate with UEs 115using the same or different wireless communications technologies. Insome cases, base station 105-f may communicate with other base stationssuch as 105-g or 105-h utilizing base station communications module1325. In some examples, base station communications module 1325 mayprovide an X2 interface within an LTE/LTE-A wireless communicationnetwork technology to provide communication between some of the basestations 105. In some examples, base station 105-f may communicate withother base stations through core network 130. In some cases, basestation 105-f may communicate with the core network 130 through networkcommunications module 1330.

The base station 105-f may include a processor 1305, memory 1315(including software (SW) 1320), transceiver 1335, and antenna(s) 1340,which each may be in communication, directly or indirectly, with oneanother (e.g., over bus system 1345). The transceivers 1335 may beconfigured to communicate bi-directionally, via the antenna(s) 1340,with the UEs 115, which may be multi-mode devices. The transceiver 1335(or other components of the base station 105-f) may also be configuredto communicate bi-directionally, via the antennas 1340, with one or moreother base stations (not shown). The transceiver 1335 may include amodem configured to modulate the packets and provide the modulatedpackets to the antennas 1340 for transmission, and to demodulate packetsreceived from the antennas 1340. The base station 105-f may includemultiple transceivers 1335, each with one or more associated antennas1340. The transceiver may be an example of a combined receiver 905 andtransmitter 915 of FIG. 9.

The memory 1315 may include RAM and ROM. The memory 1315 may also storecomputer-readable, computer-executable software code 1320 containinginstructions that are configured to, when executed, cause the processor1305 to perform various functions described herein (e.g., DRX procedureswith eCCs, selecting coverage enhancement techniques, call processing,database management, message routing, etc.). Alternatively, the software1320 may not be directly executable by the processor 1305 but beconfigured to cause the computer (e.g., when compiled and executed) toperform functions described herein. The processor 1305 may include anintelligent hardware device (e.g., a CPU, a microcontroller, an ASIC,etc.). The processor 1305 may include various special purpose processorssuch as encoders, queue processing modules, base band processors, radiohead controllers, digital signal processor (DSPs), and the like.

The base station communications module 1325 may manage communicationswith other base stations 105. The base station communications module1325 may include a controller or scheduler for controllingcommunications with UEs 115 in cooperation with other base stations 105.For example, the base station communications module 1325 may coordinatescheduling for transmissions to UEs 115 for various interferencemitigation techniques such as beamforming or joint transmission.

The components of wireless device 900, wireless device 1000, eCC DRXmodule 910, system 1200 and system 1300 may, individually orcollectively, be implemented with at least one ASIC adapted to performsome or all of the applicable functions in hardware. Alternatively, thefunctions may be performed by one or more other processing units (orcores), on at least one IC. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, an FPGA, oranother semi-custom IC), which may be programmed in any manner known inthe art. The functions of each unit may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

FIG. 14 illustrates a method 1400 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1400 may be implemented by a UE 115 or base station105 or its components as described with reference to FIGS. 1-13. Forexample, the operations of method 1400 may be performed by the eCC DRXmodule 910 as described with reference to FIGS. 9-12. In some examples,a device may execute a set of codes to control the functional elementsof the device to perform the functions described below. Additionally oralternatively, the device may perform aspects the functions describedbelow using special-purpose hardware.

At block 1405, the device may determine a CA configuration including afirst component carrier with a first channel usage procedure and asecond component carrier with a second channel usage procedure, and thefirst channel usage procedure may be different from the second channelusage procedure as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1405 may be performed by theCA configuration module 1005 as described herein with reference to FIG.10.

At block 1410, the device may determine a DRX configuration including afirst configuration for the first component carrier and a secondconfiguration for the second component carrier as described herein withreference to FIGS. 2-8. In certain examples, the operations of block1410 may be performed by the DRX configuration module 1010 as describedherein with reference to FIG. 10.

FIG. 15 illustrates a method 1500 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1500 may be implemented by a UE 115 or base station105 or its components as described with reference to FIGS. 1-13. Forexample, the operations of method 1500 may be performed by the eCC DRXmodule 910 as described with reference to FIGS. 9-12. In some examples,a device may execute a set of codes to control the functional elementsof the device to perform the functions described below. Additionally oralternatively, the device may perform aspects the functions describedbelow using special-purpose hardware. The method 1500 may alsoincorporate aspects of method 1400 of FIG. 14.

At block 1505, the device may determine a CA configuration including afirst component carrier with a first channel usage procedure and asecond component carrier with a second channel usage procedure, and thefirst channel usage procedure may be different from the second channelusage procedure as described herein with reference to FIGS. 2-8. In somecases, the second component carrier is in a shared or unlicensedspectrum. In certain examples, the operations of block 1505 may beperformed by the CA configuration module 1005 as described herein withreference to FIG. 10.

At block 1510, the device may determine a DRX configuration including afirst configuration for the first component carrier and a secondconfiguration for the second component carrier as described herein withreference to FIGS. 2-8. In certain examples, the operations of block1510 may be performed by the DRX configuration module 1010 as describedherein with reference to FIG. 10. At block 1515, the device may receivea DRX initiation message on the first component carrier based on a CCAfor the second component carrier as described herein with reference toFIGS. 2-8. In certain examples, the operations of block 1515 may beperformed by the receiver 905 as described herein with reference to FIG.9. At block 1520, the device may initiate a DRX ON duration according tothe second configuration based on the DRX initiation message asdescribed herein with reference to FIGS. 2-8. In certain examples, theoperations of block 1520 may be performed by the DRX wake module 1115 asdescribed herein with reference to FIG. 11.

FIG. 16 illustrates a method 1600 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1600 may be implemented by a UE 115 or base station105 or its components as described with reference to FIGS. 1-13. Forexample, the operations of method 1600 may be performed by the eCC DRXmodule 910 as described with reference to FIGS. 9-12. In some examples,a device may execute a set of codes to control the functional elementsof the device to perform the functions described below. Additionally oralternatively, the device may perform aspects the functions describedbelow using special-purpose hardware. The method 1600 may alsoincorporate aspects of methods 1400, and 1500 of FIGS. 14-15.

At block 1605, the device may determine a CA configuration including afirst component carrier with a first channel usage procedure and asecond component carrier with a second channel usage procedure, and thefirst channel usage procedure may be different from the second channelusage procedure as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1605 may be performed by theCA configuration module 1005 as described herein with reference to FIG.10. At block 1610, the device may determine a DRX configurationincluding a first configuration for the first component carrier and asecond configuration for the second component carrier as describedherein with reference to FIGS. 2-8. In certain examples, the operationsof block 1610 may be performed by the DRX configuration module 1010 asdescribed herein with reference to FIG. 10.

At block 1615, the device may deactivate at least one radio componentfor communication on the second component carrier according to thesecond configuration as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1615 may be performed by theDRX sleep module 1120 as described herein with reference to FIG. 11. Atblock 1620, the device may activate the at least one radio component foran ON duration according to the second configuration as described hereinwith reference to FIGS. 2-8. In certain examples, the operations ofblock 1620 may be performed by the DRX wake module 1115 as describedherein with reference to FIG. 11. At block 1625, the device may receivea control channel message on the second component carrier during the ONduration as described herein with reference to FIGS. 2-8. In certainexamples, the operations of block 1625 may be performed by the receiver905 as described herein with reference to FIG. 9.

FIG. 17 illustrates a method 1700 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1700 may be implemented by a base station 105 orits components as described with reference to FIGS. 1-13. For example,the operations of method 1700 may be performed by the eCC DRX module 910as described with reference to FIGS. 9-12. In some examples, a basestation 105 may execute a set of codes to control the functionalelements of the base station 105 to perform the functions describedbelow. Additionally or alternatively, the base station 105 may performaspects the functions described below using special-purpose hardware.The method 1700 may also incorporate aspects of methods 1400, 1500, and1600 of FIGS. 14-16.

At block 1705, the base station 105 may determine a CA configurationincluding a first component carrier with a first channel usage procedureand a second component carrier with a second channel usage procedure,and the first channel usage procedure may be different from the secondchannel usage procedure as described herein with reference to FIGS. 2-8.In certain examples, the operations of block 1705 may be performed bythe CA configuration module 1005 as described herein with reference toFIG. 10. At block 1710, the base station 105 may determine a DRXconfiguration including a first configuration for the first componentcarrier and a second configuration for the second component carrier asdescribed herein with reference to FIGS. 2-8. In certain examples, theoperations of block 1710 may be performed by the DRX configurationmodule 1010 as described herein with reference to FIG. 10. At block1715, the base station 105 may configure a wireless device with the CAconfiguration and the DRX configuration as described herein withreference to FIGS. 2-8. In certain examples, the operations of block1715 may be performed by the CA configuration module 1005 as describedherein with reference to FIG. 10.

FIG. 18 illustrates a method 1800 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1800 may be implemented by a UE 115 or base station105 or its components as described with reference to FIGS. 1-13. Forexample, the operations of method 1800 may be performed by the eCC DRXmodule 910 as described with reference to FIGS. 9-12. In some examples,a device may execute a set of codes to control the functional elementsof the device to perform the functions described below. Additionally oralternatively, the device may perform aspects the functions describedbelow using special-purpose hardware. The method 1800 may alsoincorporate aspects of methods 1400, 1500, 1600, and 1700 of FIGS.14-17.

At block 1805, the device may determine a CA configuration including afirst component carrier with a first channel usage procedure and asecond component carrier with a second channel usage procedure, and thefirst channel usage procedure may be different from the second channelusage procedure as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1805 may be performed by theCA configuration module 1005 as described herein with reference to FIG.10. At block 1810, the device may determine a DRX configurationincluding a first configuration for the first component carrier and asecond configuration for the second component carrier as describedherein with reference to FIGS. 2-8. In some cases, each ON duration ofthe second configuration is extended to include a final DL TTI for a DLburst of the second component carrier. In certain examples, theoperations of block 1810 may be performed by the DRX configurationmodule 1010 as described herein with reference to FIG. 10.

At block 1815, the device may receive an indication of a scheduled ULburst during the final DL TTI of an ON duration of the secondconfiguration as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1815 may be performed by thereceiver 905 as described herein with reference to FIG. 9. At block1820, the device may transmit an ACK for a HARQ process associated withthe second component carrier based on the indication as described hereinwith reference to FIGS. 2-8. In certain examples, the operations ofblock 1820 may be performed by the HARQ module 1125 as described hereinwith reference to FIG. 11.

FIG. 19 illustrates a method 1900 for DRX procedures with eCCs inaccordance with various aspects of the present disclosure. Theoperations of method 1900 may be implemented by a base station 105 orits components as described with reference to FIGS. 1-13. For example,the operations of method 1900 may be performed by the eCC DRX module 910as described with reference to FIGS. 9-12. In some examples, a basestation 105 may execute a set of codes to control the functionalelements of the base station 105 to perform the functions describedbelow. Additionally or alternatively, the base station 105 may performaspects the functions described below using special-purpose hardware.The method 1900 may also incorporate aspects of methods 1400, 1500,1600, 1700, and 1800 of FIGS. 14-18.

At block 1905, the base station 105 may determine a CA configurationincluding a first component carrier with a first channel usage procedureand a second component carrier with a second channel usage procedure,and the first channel usage procedure may be different from the secondchannel usage procedure as described herein with reference to FIGS. 2-8.In certain examples, the operations of block 1905 may be performed bythe CA configuration module 1005 as described herein with reference toFIG. 10. At block 1910, the base station 105 may determine a DRXconfiguration including a first configuration for the first componentcarrier and a second configuration for the second component carrier asdescribed herein with reference to FIGS. 2-8. In certain examples, theoperations of block 1910 may be performed by the DRX configurationmodule 1010 as described herein with reference to FIG. 10. At block1915, the base station 105 may rate match a data transmission on thefirst component carrier based on symbol level interruption of the firstcomponent carrier associated with an ON duration associated with thesecond configuration as described herein with reference to FIGS. 2-8. Incertain examples, the operations of block 1915 may be performed by therate matching module 1130 as described herein with reference to FIG. 11.

Thus, methods 1400, 1500, 1600, 1700, 1800, and 1900 may provide for DRXprocedures with eCCs. It should be noted that methods 1400, 1500, 1600,1700, 1800, and 1900 describe possible implementation, and that theoperations and the steps may be rearranged or otherwise modified suchthat other implementations are possible. In some examples, aspects fromtwo or more of the methods 1400, 1500, 1600, 1700, 1800, and 1900 may becombined.

The description herein provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.The terms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases 0 and A are commonly referred toas CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM). An OFDMA system may implement a radio technologysuch as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA andE-UTRA are part of Universal Mobile Telecommunications system (UMTS).3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are new releasesof Universal Mobile Telecommunications System (UMTS) that use E-UTRA.UTRA, E-UTRA, UMTS, LTE, LTE-A, and Global System for Mobilecommunications (GSM) are described in documents from an organizationnamed “3rd Generation Partnership Project” (3GPP). CDMA2000 and UMB aredescribed in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2). The techniques described herein may beused for the systems and radio technologies mentioned above as well asother systems and radio technologies. The description herein, however,describes an LTE system for purposes of example, and LTE terminology isused in much of the description above, although the techniques areapplicable beyond LTE applications.

In LTE/LTE-A networks, including such networks described herein, theterm evolved node B (eNB) may be generally used to describe the basestations. The wireless communications system or systems described hereinmay include a heterogeneous LTE/LTE-A network in which different typesof eNBs provide coverage for various geographical regions. For example,each eNB or base station may provide communication coverage for a macrocell, a small cell, or other types of cell. The term “cell” is a 3GPPterm that can be used to describe a base station, a carrier or componentcarrier associated with a base station, or a coverage area (e.g.,sector, etc.) of a carrier or base station, depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a HomeeNodeB, or some other suitable terminology. The geographic coverage areafor a base station may be divided into sectors making up only a portionof the coverage area. The wireless communications system or systemsdescribed herein may include base stations of different types (e.g.,macro or small cell base stations). The UEs described herein may be ableto communicate with various types of base stations and network equipmentincluding macro eNBs, small cell eNBs, relay base stations, and thelike. There may be overlapping geographic coverage areas for differenttechnologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers). A UE may be able to communicate with varioustypes of base stations and network equipment including macro eNBs, smallcell eNBs, relay base stations, and the like.

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The DL transmissions described herein may also be called forward linktransmissions while the uplink transmissions may also be called reverselink transmissions. Each communication link described herein—including,for example, wireless communications systems 100 and 200 of FIGS. 1 and2—may include one or more carriers, where each carrier may be a signalmade up of multiple sub-carriers (e.g., waveform signals of differentfrequencies). Each modulated signal may be sent on a differentsub-carrier and may carry control information (e.g., reference signals,control channels, etc.), overhead information, user data, etc. Thecommunication links described herein (e.g., communication links 125 ofFIG. 1) may transmit bidirectional communications using frequencydivision duplex (FDD) (e.g., using paired spectrum resources) or timedivision duplex (TDD) operation (e.g., using unpaired spectrumresources). Frame structures may be defined for FDD (e.g., framestructure type 1) and TDD (e.g., frame structure type 2).

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “and/or,” when used in a list of two or more items, means thatany one of the listed items can be employed by itself, or anycombination of two or more of the listed items can be employed. Forexample, if a composition is described as containing components A, B,and/or C, the composition can contain A alone; B alone; C alone; A and Bin combination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates adisjunctive list such that, for example, a list of “at least one of A,B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B andC).

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media cancomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notto be limited to the examples and designs described herein but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method of wireless communication, comprising:determining a carrier aggregation (CA) configuration comprising a firstcomponent carrier with a subcarrier spacing (SCS) and a second componentcarrier with a second SCS different than the first SCS; performingdiscontinuous reception (DRX) on the first component carrier based on afirst configuration; and performing DRX on the second component carrierbased on a second configuration, a DRX timer duration of the secondcomponent carrier being different than a DRX timer duration of the firstcomponent carrier; receiving a DRX command message for the secondcomponent carrier on the first component carrier; transitioning to a DRXOFF state on the second component carrier based at least in part on theDRX command message.
 2. The method of claim 1 further comprising:receiving a DRX initiation message; and wherein the performing DRX onthe second component carrier comprises initiating a DRX ON durationaccording to the second configuration based at least in part on the DRXinitiation message.
 3. The method of claim 1, wherein the performing DRXon the second component carrier comprises deactivating at least oneradio component for communication on the second component carrier for atime period according to the second configuration; and furthercomprising: activating the at least one radio component for an ONduration after the time period has elapsed; and receiving a controlchannel message on the second component carrier during the ON duration,wherein the control channel message indicates a burst length during theON duration.
 4. The method of claim 1, wherein the second configurationcomprises an ON duration corresponding to a subcarrier spacing of thesecond component carrier.
 5. The method of claim 4, wherein the ONduration is configured by a DL control information directed toward auser equipment.
 6. An apparatus for wireless communication, comprising:means for determining a carrier aggregation (CA) configurationcomprising a first component carrier with a first subcarrier spacing(SCS) and a second component carrier with a second SCS different thanthe first SCS; means for performing discontinuous reception (DRX) on thefirst component carrier based on a first configuration; means forperforming DRX on the second component carrier based on a secondconfiguration, a DRX timer duration of the second component carrierbeing different than a DRX timer duration of the first componentcarrier; and means for receiving a DRX command message for the secondcomponent carrier on the first component carrier; wherein the means forperforming DRX on the second component carrier is configured totransition to a DRX OFF state on the second component carrier based atleast in part on the DRX command message.
 7. The apparatus of claim 6,wherein the means for receiving a DRX command message is furtherconfigured to: receive a DRX initiation message; and wherein the meansfor performing DRX on the second component carrier is configured toinitiate a DRX ON duration according to the second configuration basedat least in part on the DRX initiation message.
 8. The apparatus ofclaim 6, wherein the means for performing DRX on the second componentcarrier deactivates at least one radio component for communication onthe second component carrier for a time period according to the secondconfiguration; wherein the means for performing DRX on the secondcomponent carrier activates the at least one radio component for an ONduration after the time of time has elapsed; and means for receiving aDRX command message is further configured to receive a control channelmessage on the second component carrier during the ON duration, whereinthe control channel message indicates a burst length during the ONduration.
 9. The apparatus of claim 6, wherein the second configurationcomprises an ON duration associated with the second SCS.
 10. Theapparatus of claim 9, wherein the ON duration is configured by a DLcontrol information directed toward the apparatus.
 11. An apparatus forwireless communication, comprising: a processor; memory in electroniccommunication with the processor; and instructions stored in the memoryand operable, when executed by the processor, to cause the apparatus to:determine a carrier aggregation (CA) configuration comprising a firstcomponent carrier with a subcarrier spacing (SCS) and a second componentcarrier with a second SCS different than the first SCS; performdiscontinuous reception (DRX) on the first component carrier based on afirst configuration; and perform DRX on the second component carrierbased on a second configuration, a DRX timer duration of the secondcomponent carrier being different than a DRX timer duration of the firstcomponent carrier; receive a DRX command message for the secondcomponent carrier on the first component carrier; transition to a DRXOFF state on the second component carrier based at least in part on theDRX command message.
 12. The apparatus of claim 11, wherein theinstructions are executable to: receive a DRX initiation message; andwherein the performing DRX on the second component carrier comprisesinitiating a DRX ON duration according to the second configuration basedat least in part on the DRX initiation message.
 13. The apparatus ofclaim 11, wherein the performing DRX on the second component carriercomprises deactivating at least one radio component for communication onthe second component carrier for a time period according to the secondconfiguration; wherein the instructions further: activate the at leastone radio component for an ON duration after the time period haselapsed; and receive a control channel message on the second componentcarrier during the ON duration, wherein the control channel messageindicates a burst length during the ON duration.
 14. The apparatus ofclaim 11, wherein the second configuration comprises an ON durationassociated with the second SCS.
 15. The apparatus of claim 14, whereinON duration is configured by a DL control information directed towardthe apparatus.
 16. A non-transitory computer-readable medium storingcode for wireless communication, the code comprising instructionsexecutable to: determine a carrier aggregation (CA) configurationcomprising a first component carrier with a subcarrier spacing (SCS) anda second component carrier with a second SCS different than the firstSCS; perform discontinuous reception (DRX) on the first componentcarrier based on a first configuration; and perform DRX on the secondcomponent carrier based on a second configuration, a DRX timer durationof the second component carrier being different than a DRX timerduration of the first component carrier; receive a DRX command messagefor the second component carrier on the first component carrier;transition to a DRX OFF state on the second component carrier based atleast in part on the DRX command message.
 17. The non-transitorycomputer-readable medium of claim 16, wherein the instructions arefurther executable to: receive a DRX initiation message; and wherein theperforming DRX on the second component carrier comprises initiating aDRX ON duration according to the second configuration based at least inpart on the DRX initiation message.
 18. The non-transitorycomputer-readable medium of claim 16, wherein the performing DRX on thesecond component carrier comprises deactivating at least one radiocomponent for communication on the second component carrier for a timeperiod according to the second configuration; and the instructionsfurther: activate the at least one radio component for an ON durationafter the time period has elapsed; and receive a control channel messageon the second component carrier during the ON duration, wherein thecontrol channel message indicates a burst length during the ON duration.19. The non-transitory computer-readable medium of claim 16, wherein thesecond configuration comprises an ON duration associated with the secondSCS.
 20. The non-transitory computer-readable medium of claim 19,wherein the ON duration is configured by a DL control information.